1. Field of Endeavor
The present invention relates to a burner for a gas turbine and a method for feeding a gaseous fuel into a burner.
2. Brief Description of the Related Art
In particular, the present invention relates to a sequential combustion gas turbine, i.e., a gas turbine having a compressor which generates a main flow of compressed air and feeds it to a first burner, wherein a fuel is injected to form a mixture.
The mixture is combusted in a combustion chamber and is expanded in a high pressure turbine. The hot gases (which come out from the high pressure turbine and are still rich in oxygen) are then fed to a second burner, wherein a further fuel is injected to form a mixture that is combusted in a second combustion chamber to generate hot gases that are expanded in a low pressure turbine.
In particular, the present invention can relate to the second burner.
As known in the art, the temperature of the hot gases going out from the second combustion chamber allows a good efficiency and, at the same time, also low NOx emissions to be achieved.
Nevertheless, in order to increase the efficiency of the gas turbines, the temperature of the hot gases going out from the second combustion chamber should be increased.
Increasing the temperature in the second combustion chamber inevitably causes an increase of the NOx emissions that, on the contrary, should be kept as low as possible.